Hand level



NOV. 22, 1938. M, LEUPOLD 2,137,776

HAND LEVEL Filed Sept. 14, 1936 1 4 ig z y 1114mm" Impala Patented Nov.22, 1938 2,137,776

UNITED STATES PATENT OFFICE HAND LEVEL Marcus Leupold, Portland, Oreg.

Application September 14, 1936, Serial No. 100,742

Claims. (01. 33-73) This invention relates to leveling instruments fromone edge to another on the frame, which suitable for determining extentof elevation or permits the scale plates to be readily insertabledepression, and; more particularly to leveling into and removable fromthe groove by an endinstruments of the hand or pocket type com wisesliding action. Furthermore, the groove is 5 monly known as Abneylevels. not only made deeper than the thickness of one Levels of' thistype are used in a variety of scale plate to permit reception of morethan one 5 ways and for different kinds of work as, for plate, but isless deep than the combined thickexample, in surveying and measuringsection lines ness of the pair of scale plates, so that when the andboundaries and other public land measureplates are arranged insuperimposed position in w ments, which are generally measured in chainsof the groove they extend slightly above the exposed 1 sixty-six feet,or in locating trails, roads, ditches, surface of the frame and createaslight resistance and the like, in which case the percentage of to therotating or oscillating movement of the grade must be determined. Inview of this and usual indicating arm.

in order to avoid the necessity of employing two A further understandingof the invention will a different levels each having a scale adapted.for a be gained by examining the accompanying drawdifferent type ofmeasurement, it is common pracing, in which like numerals refer to likeparts,

tice to provide two scales on each level, and in and in which:

fact extensive users of these instruments, such Figure 1 represents aside elevation of the comas the Federal Government, require theprovision plete hand level;

of two scales in their bids for supply, e. g. a topo- Figure 2 is a planview; graphic scale,whichis based upon an angular unit Figure 3 is ahorizontal section taken on the represented by the ratio of one unitvertically to line 3-3 of Figure 2; and sixty-six units horizontally,and a percent scale, Figure 4 is a vertical transverse section takenwhich indicates the extent. of grade by percentage. on the line 4-4 ofFigure 2.

In satisfying this requirement for two separate Referring to the drawingthe numeral I0 repre scales on one instrument, it has been customarysents a frame member which serves to fixedly to provide a scale on eachside of the supporting support on one side thereof along its lowerporframe of the level, each scale having different tion a sight tube Hand has rotatably mounted indicia thereon to adapt it for differentkinds of on its upper middle portion an arm 12 which measurement. Suchan arrangement, however, serves. to indicate the angle of elevation ordehas proved to be very unsatisfactory, as each time pression. Upon thisarm is fixed a bubble mountit was required to employ a different scale,it was. ing, indicated generally at l3, which'comprises a necessary tonot only reverse the arc-like frame supporting arm l4 provided at itsupper portion but the bubble mounting as well, and this was with a pairof horizontally extending lugs l5 and always attended with considerableloss of time I6 from which the bolts or screws 11 and I8 deand troublein view of the necessity of entirely pend. These bolts, are eachprovided with a pair re-adjusting the instrument. of nuts l9 and 20 and2| and 22 respectively,

It is accordingly a principal object of this inwhich serve to supportand position a tubular casvention to provide a scale arrangement whiching 23 constituting a protective mounting for the permits quick changesof scales without the bubble, containing vial 24. Arm I2 is rotatablynecessity of re-adjusting the leveling mechanism mounted on a bolt 25positioned in the apex in and which otherwise avoids the disadvantagesthe upper portion 26 of frame I!) and fastened referred to. A furtherobject of the invention is thereto by the nut 21, and is provided with ato provide means for storing and retaining apair suitable knob orsimilar device 28 near its lower of scale plates in the correct positionfor use and end for moving the arm and vial 24 in accordance in aconveniently removable and replaceable with the elevation or depressionbeing measured. manner. Fitted for telescopically sliding action in oneThese and other objects are accomplished by end of the sight tube ll isa tube 29 which has an providing a relatively shallow groove on theeye-piece 30 fastened on its outer end and a semiw exposed face of thesupporting frame of the in circular lens piece 3! provided on its innerend. '50- strument, which is not only capable of acting as In the middleportion of tube 29 is a longitudia guide for the application and removalof a pair nally extending slot 32 which cooperates with the of scaleplates but also receiving and retaining screw 33 in positioning tube 29and. lens 3| in such plates in operating position. The groove is thesight tube II and permitting limited longimost suitably of an arcuateshape and extends tudinal reciprocation of these parts therein. As- 55cordingly by sliding tube 29 within the limits allowed by slot 32 andscrew '33 it is possible to focus lens 3| to obtain the clearest view ofthe bubble in vial 24.

In the opposite end of tube H is another tube 34 which is cut off at anangle of 45 at its inner end 35. Half closing this end and substantiallyflush with its edges, i. e. also at an angle of 45, is a semi-ellipticalmirror 36, while at the opposite end of tube 34 is a horizontal sightstrip 31 which together with the straight side of the mirror forms acentral point of sight as viewed from eye piece 30. Tube 34 may bereciprocated in and out of tube 1 l and is guided in this movement bythe screw 38 which is slidable in slot 39 and may be tightened to lockthe tubes together. Thus, by sliding tube 34 to the desired extent ineither direction within tube II, it is possible to adjust mirror 36 inthe best position below vial 24 for accurate viewing of the bubblethrough eye piece and the aperture 40.

Frame [0 is also provided on its exposed vertical surface withrelatively flat and wide arcuateshaped groove which extends completelyfrom top edge to top edge thereof and thus permits the endwise insertionof a pair of scale plates 42 which may be placed in position for use bya simple circular sliding action. Plates 42 are made of thinresilientstrip metal and are each provided with an aperture adjacenteach end. When the plates are in correct position for angularmeasurement these apertures are in alignment with suitable apertures inframe It) and together therewith are adapted to receive the screws 43and 44 which serve not only to retain the plates in the desired positionduring normal use of the leveling instrument but also as stop membersfor arm l2. The plates extend slightly above the surface of frame I0,when they are in superposed relation, and thus provide a certaindesirable frictional resistance to the movement of indicator arm l2.They are made sufficiently thin, however, to permit two of them to besimultaneously guided and retained by groove 4|, and yet, being -made ofresilient metal, either one of them alone is capable of substantiallyfilling the groove.

In using a level of this type together with the improvement describedherein, the scale plates are first applied by sliding into position andare 1 then fasten-ed with the desired plate uppermost.

A point or object on a level rod or staff positioned above the ground adistance equivalent to the height or distance of the leveling instrumentfrom the ground is then sighted, and arm 12 is moved until the image ofthe bubble in mirror 36 appears to be in proper alignment with the hairline or sight strip 31. The angle through which arm I2 must be movedalong'the scale in order to bring about these conditions is anindication to the observer of the angle or number of points of thebottom one before fastening them again. In

either case the withdrawal or insertion of the plate or plates issimple, and may be accomplished Without disturbing the adjustment of arml2 and the bubble mounting owing to the easy Lsliding action.

Thus the present invention has provided an improvement in Abney handlevels which permits a variety of measurements to be made with the sameinstrument using different types of scales and makes it possible tochange scales with great dispatch and without the necessity of takingthe instrument apart or in any way altering its adjustment. The scalesmay be conveniently stored in the groove in which they are used, and itis feasible to take measurements with either one or both of the scaleplates in position, it being preferable, however, to have both in placeowing to the slight braking action they exert on the indicator arm.

It is within the contemplation of the invention to employ any othermeans of fastening the plates to the frame as a substitute for the boltsor screws hereinbefore referred to, as it is merely essential that theplates be fastened in the correct position for measurement and yet areconveniently and quickly removable. Furthermore, it is to be understoodthat the invention is capable of other modifications and applicationsand. should therefore be limited only by the scope of the appendedclaims.

I claim:

1. In a leveling instrument of the class described, a frame memberprovided with an arcuate groove, and a separate and separable scalemember snugly fitting in and retained by said groove, said scale memberbeing removable from said groove and said groove having in its bottomportion scale indicia which are different than those on the separablescale member, whereby upon removing said separable scale member adifferent scale is exposed.

2. In a leveling instrument of the class described, a frame member, aseparate and separable scale member, and an arcuate groove on the framefor removably holding and positioning said scale member, said grooveextending from one edge to another edge of said frame, and having in itsbottom portion scale indicia which are different than those on theseparable scale member whereby the scale member may be readily placedinto and removed from operative position by anendwise sliding movementto cover and expose respectively the indicia in said groove.

3. In a leveling instrument in the class described, a frame member, anindicating arm supported on the frame member, a separate and separablescale member, and a groove on the frame for removably holding the scalemember in cooperative position with said arm, said groove extending fromone edge to another edge of said frame and having in its bottom portionscale indicia which are different than those on the separable scalemember, and said indicating arm being firmly held against the frame andbeing frictionally m ovable therealong, whereby said arm may beadjustably positioned with respect to said scale member and said scalemember may be removed to expose the scale indicia in said groove withoutaltering the adjustment of said arm.

4. In a leveling instrument of the class described, a frame member inthe form of a spider having an arcuate portion and a pivotal center, anindicating arm oscillatable about said center, an arcuate groove in saidarcuate portion concentric with said center, and a scale membersubstantially fitting in said groove in cooperative position with saidarm and slidably removable therefrom, said groove having in its bottomportion scale indicia which are different than those on the removablescale member, whereby upon removing said removable scale member adifferent scale is exposed.

5. In a leveling instrument of the class described, a frame member, aseparate and separable scale member, and means for removably fasteningsaid scale member in a predetermined position upon the surface of saidframe member, said frame member having on the portion of its surfacebeneath said scale member scale indicia which are different than thoseon the separable scale member, whereby upon removing said scale 5 membera different scale is exposed.

MARCUS LEUPOLD.

